Contaminated soil represents a major environmental problem in countries with a long industrial history. Organic and inorganic contaminants are a health hazard to the local population, threaten ground water resources, and restrict land use. Merinonita\'s solution is based on a closed bioreactor built into a sea container for flexibility and easy transportation.
Biological methods have been used for the remediation of contaminated soil for decades. Most organic contaminants are biodegradable under the appropriate conditions, and bioremediation - or soil composting - is widely used, particularly for treating soil contaminated with mineral oil.
This is typically carried out in open soil windrows. Although relatively effective if managed correctly, open composting has a number of serious disadvantages, however.
Cold weather can easily shorten the annual \'biodegradation season\' in some countries to no more than six months a year. It is also difficult to control soil moisture and the evaporation of volatile compounds. Oxygen has to be delivered by mixing the windrows, and a treatment field must be specially constructed to minimise leachate problems.
|The BRCsoil reactor - a cost-effective|
and safe way of treating contaminated soil.
Merinonita\'s solution to the problem takes the form of a closed bioreactor - the BRCsoil reactor. Built into a sea container for easy transportation, the BRCsoil reactor is equipped with automated heating, aeration, and water control systems, and is water- and gas-tight for maximum safety.
The closed design of the BRCsoil reactor means that the composting process is unaffected by the outdoor temperature, and key process parameters (temperature, oxygen, moisture) are fully controllable, which speeds up throughput times. The use of a closed system also minimises environmental impact at the treatment site, while the modular design brings flexibility, as the number of reactors can be increased or reduced as treatment requirements change.
The capacity of the BRCsoil reactor depends on the type and concentration of the contaminant, as well as the target concentration. In the case of oil-contaminated soil such as often found at service stations, with an oil concentration of between 2,000 and 4,000 mg/kg, a BRCsoil40 reactor can process between 600 and 1,000 tonnes of soil a year.
Remediation efficiency is typically six-fold higher using the BRCsoil reactor than with open composting windrows. (Graph)